This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, w...This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, we use two videos and three voices (two voices for one video and one voice for the other video). We also investigate influences of silence periods in the voices and temporal relations between the voices and videos (called the tightly-coupled and loosely-coupled contents here). The voices are spoken by a teacher according to the videos. Each subject as a student assesses the group synchronization quality by watching each lecture video and the corresponding explanation voice, and then the subject answers whether he/she perceives the group synchronization error or not. As a result, assessment results illustrate that silence periods mitigate the perception rate of the error, and we can also find that we can more easily perceive the error for tightly-coupled contents than loosely-coupled ones.展开更多
In view of the major defect of the traditionalteacher correction,this paper introduces a new ap-proach to error correction—group error correction,inwhich learners’ role in learning language is greatly in-creased.Gro...In view of the major defect of the traditionalteacher correction,this paper introduces a new ap-proach to error correction—group error correction,inwhich learners’ role in learning language is greatly in-creased.Group error correction can be used to correcterrors in students’ oral work,group work and writtenwork,both in class and after class.Half a year’spractice of group error correction shows that it helpsincrease learner involvement in the teaching and learn-ing process,stimulate learner motivation in learningthe foreign language,raise the learners’ awareness oferrors,facilitate learners’ learning of the foreign lan-guage,relieve the teacher’s burden,and helps theteacher make better teaching plans.Error correction is an enormously complex pro-cess(Ellis,1994,p585).As for which is the most ef-fective method to correct errors,researchers havenot reached an agreement.Therefore more effortsneed to be made in this field.展开更多
A non-unitary non-coherent space-time code which is capable of achieving full algebraic diversity is proposed based on full diversity space-time block coding, The error performance is optimized by transforming the non...A non-unitary non-coherent space-time code which is capable of achieving full algebraic diversity is proposed based on full diversity space-time block coding, The error performance is optimized by transforming the non-unitary space-time code into unitary space-time code, By exploiting the desired structure of the proposed code, a grouped generalized likelihood ratio test decoding algorithm is presented to overcome the high complexity of the optimal algorithm, Simulation results show that the proposed code possesses high spectrum efficiency in contrast to the unitary space-time code despite slight loss in the SNR, and besides, the proposed grouped decoding algorithm provides good tradeoff between performance and complexity,展开更多
文摘This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, we use two videos and three voices (two voices for one video and one voice for the other video). We also investigate influences of silence periods in the voices and temporal relations between the voices and videos (called the tightly-coupled and loosely-coupled contents here). The voices are spoken by a teacher according to the videos. Each subject as a student assesses the group synchronization quality by watching each lecture video and the corresponding explanation voice, and then the subject answers whether he/she perceives the group synchronization error or not. As a result, assessment results illustrate that silence periods mitigate the perception rate of the error, and we can also find that we can more easily perceive the error for tightly-coupled contents than loosely-coupled ones.
文摘In view of the major defect of the traditionalteacher correction,this paper introduces a new ap-proach to error correction—group error correction,inwhich learners’ role in learning language is greatly in-creased.Group error correction can be used to correcterrors in students’ oral work,group work and writtenwork,both in class and after class.Half a year’spractice of group error correction shows that it helpsincrease learner involvement in the teaching and learn-ing process,stimulate learner motivation in learningthe foreign language,raise the learners’ awareness oferrors,facilitate learners’ learning of the foreign lan-guage,relieve the teacher’s burden,and helps theteacher make better teaching plans.Error correction is an enormously complex pro-cess(Ellis,1994,p585).As for which is the most ef-fective method to correct errors,researchers havenot reached an agreement.Therefore more effortsneed to be made in this field.
基金Supported by the National Natural Science Foundation of China (Grant No. 60372055)the National Doctoral Foundation of China (Grant No. 20030698027)
文摘A non-unitary non-coherent space-time code which is capable of achieving full algebraic diversity is proposed based on full diversity space-time block coding, The error performance is optimized by transforming the non-unitary space-time code into unitary space-time code, By exploiting the desired structure of the proposed code, a grouped generalized likelihood ratio test decoding algorithm is presented to overcome the high complexity of the optimal algorithm, Simulation results show that the proposed code possesses high spectrum efficiency in contrast to the unitary space-time code despite slight loss in the SNR, and besides, the proposed grouped decoding algorithm provides good tradeoff between performance and complexity,
